Catalan separatist leader Puigdemont arrested in Germany

Catalan separatists and supporters of the region's right to hold a referendum on independence from Spain have held a rally backing more than 700 mayors facing the threat of arrest.

The mayors have been called in for questioning by prosecutors for agreeing to facilitate the vote locally.

They could be arrested if they do not attend and prosecuted for using public funds if they help stage the ballot.

Madrid has promised to block the vote, saying it is unconstitutional.

Catalonia's regional government insists it will take place as scheduled despite a growing clampdown by the Spanish state.

Mayors turned out with their staves of office

Some of the mayors gathered with Catalan President Carles Puigdemont outside the headquarters of the regional government, the Generalitat Palace, as supporters waved the lone-star flag of the independence movement.

"We stand firm against threats, censorship and prosecution and repeat this: we want to be a free country," Mr Puigdemont told the crowd, according to a tweet by the Catalan National Assembly grassroots independence movement.

Chants of "We will vote" could be heard from the crowd.

Barcelona Mayor Ada Colau, who supports the right to hold the referendum, also turned up.

"It's a disgrace that we have a government that is incapable of dialogue and instead dedicates itself to pursuing and intimidating mayors and the media," she said.

Ms Colau announced on Thursday that people in Barcelona would be able to vote without civil servants involved risking their jobs but did not explain how.

'It won't happen'

On Friday, the Spanish government gave the regional government 48 hours to abandon its "illegal" referendum plans or lose budgetary powers.

"If, 48 hours from now, there's no compromise that falls within the law, from then on the Spanish government will take over responsibility for making Catalonia's payments," Spanish Prime Minister Mariano Rajoy later told a meeting of his Popular Party in Barcelona.

"My friends, I say this both calmly and firmly: there will be no referendum, it won't happen."

Mr Rajoy also announced that police from Spain's national Guardia Civil force had seized 100,000 referendum posters.

No government in the world, he said, could accept one of its regions unilaterally scrapping the nation's constitution and its laws.

Attempts to block the official referendum website have continued.

Thousands of ballot boxes are said to have been hidden by referendum supporters. Police have been hunting for them but Toni Castejon, spokesman for the Catalan police force, admitted "right now, we have no idea where they are", the Reuters news agency reported.

Tensions were already high before Josep Maria Jové, number two in the Catalan vice-presidency, and others were held.

Thousands of Catalans took to the streets in protest and the regional leader complained of a power grab.

Spanish Prime Minister Mariano Rajoy said the state had been forced to act.

Catalonia's separatist government is defying a Constitutional Court order to halt the planned 1 October vote, which has been condemned by the Madrid government as illegal.

A sea of protesters filled the Gran Via and other streets as police searched the Catalan economy ministry

Wednesday's operation targeting over 20 ministries and institutions was a dramatic intensification of Spain's attempt to stop the vote taking place. At least six million ballot papers were found in a warehouse outside Barcelona, reports said.

And in a separate move Spain's finance minister, Cristóbal Montoro, said the national government was now set to take control of a large part of Catalonia's public finances.

After an emergency cabinet meeting Catalan President Carles Puigdemont accused the Madrid government of "de facto" suspending the region's autonomy and imposing a state of emergency.

Why is Spain cracking down?

Eleven days ahead of the planned vote on 1 October, the national government has made its biggest move yet to stop it happening.

Spain did not stop an earlier vote taking place in November 2014, but this time the Catalan leadership plans a declaration of independence within 48 hours of a Yes vote. Spain's government has been backed by the Constitutional Court, which has suspended the referendum law passed by the Catalan parliament.

Scuffles broke out on Tuesday when demonstrators in Terrassa tried to stop a raid targeting voting material

Mr Rajoy said the regional government had been warned that they were destroying Spain's national sovereignty, "There's no democratic state in the world that would accept what these people are planning," he said. He urged the Catalan president to comply with the law and put his secessionist challenge into "reverse gear".

Several ministries in Barcelona were raided on Wednesday, including the economy, foreign affairs, telecoms, social affairs and presidency buildings. Among those detained were officials from the economy ministry, run by Catalan Vice-President Oriol Junqueras, as well as figures from other departments.

Police were searching for computer equipment and any documentation linked to the planned vote. The day before, they seized some 45,000 envelopes with the Catalan government's logo from a private delivery company in Terrassa, north-west of Barcelona.

On Friday, the Spanish finance minister gave Oriol Junqueras a deadline to call off the vote or see funding for essential services in Catalonia taken over by Madrid. A letter was sent to Mr Junqueras late on Tuesday reminding him the deadline had passed.

Tens of thousands of people are expected to attempt to vote on Sunday.

As a result, Spanish authorities are now stepping up their attempts to stop the ballot taking place.

Authorities in Madrid have sent thousands of police to the region to stop the referendum - declared illegal by Spain's constitutional court. They are being assisted by the Catalan regional police force, the Mossos d'Esquadra.

Police have now occupied the regional government's telecommunications centre.

Police have also been ordered to clear schools occupied by activists aiming to ensure the buildings can be used for voting.

Many of those inside the schools are parents and their children, who remained in the buildings after the end of lessons on Friday. Some told Reuters news agency that police had told them they could stay as long as they were not doing anything connected to Sunda's vote.

Laia, a 41-year-old sociologist who is staying in a Barcelona school this evening, said the police had visited four times.

"They read us out the part of the court order that says no activities related to the preparation of the banned referendum are allowed," she told Reuters.

What is the basis for the vote?

Catalonia, a wealthy region of 7.5 million people in north-eastern Spain, has its own language and culture.

It also has a high degree of autonomy, but is not recognised as a separate nation under the Spanish constitution.

Pressure for a vote on self-determination has grown over the past five years as austerity has hit the Spanish economy and people hard.

But Spanish unionists argue Catalonia already enjoys broad autonomy within Spain, along with other regions like the Basque Country and Galicia.

Will the vote go ahead?

Officers have been visiting the locations due to be used as polling stations, as well as seizing items such as ballot papers, while prosecutors have ordered the closure of websites linked to the vote and the arrest of officials organising the referendum.

But Catalan leader Carles Puigdemont told Reuters that the referendum would go ahead.

"Everything is prepared at the more than 2,000 voting points so they have ballot boxes and voting slips, and have everything people need to express their opinion," he said.

Why is Madrid so opposed?

Spanish Prime Minister Mariano Rajoy stared down Catalan secessionists when they held a trial referendum in 2014, offering no concessions to their demand for a legal vote.

He has pledged to stop the 2017 vote, saying it goes against the constitution which refers to "the indissoluble unity of the Spanish Nation, the common and indivisible homeland of all Spaniards".

Catalonia in numbers

16% of Spain's population live in Catalonia

25.6% of Spain's exports come from Catalonia

19% of Spain's GDP is produced in Catalonia

20.7% of foreign investment in Spain goes to Catalonia

35.3% of Catalonia's GDP is debt

Ministry of Economy, Industry and Competitiveness, Eurostat, Bank of Spain

Central government spokesman Iñigo Mendez de Vigo accused the Catalan government of being inflexible and one-sided but it is a charge Catalan nationalists throw back at Madrid itself.

Despite the tension in the region, demonstrations by independence campaigners have been largely peaceful.

"I don't believe there will be anyone who will use violence or who will want to provoke violence that will tarnish the irreproachable image of the Catalan independence movement as pacifist," Mr Puigdemont said.

The Guardia Civil said it was "resisting harassment and provocation" while carrying out its duties "in defence of the law"

One voter, Júlia Graell, told the BBC that "police started to kick people, young and old", adding: "Today, I have seen the worst actions that a government can do to the people of its own country."

In Girona, riot police smashed their way into a polling station where Mr Puigdemont was due to vote, and forcibly removed those looking to place their ballots. Mr Puigdemont was able to vote at another polling station.

The BBC's Tom Burridge, in Barcelona, witnessed police being chased away from one polling booth after they had raided it.

Since Friday, thousands of people have occupied schools and other buildings designated as polling stations in order to keep them open.

Many of those inside were parents and their children, who remained in the buildings after the end of lessons on Friday and bedded down in sleeping bags on gym mats.

In some areas, farmers positioned tractors on roads and in front of polling station doors, and school gates were taken away to make it harder for the authorities to seal buildings off. Firefighters have acted as human shields between police and demonstrators.

Referendum organisers had called for peaceful resistance to any police action.

Meanwhile, FC Barcelona's match against Las Palmas was played behind closed doors, after Barcelona said the football league refused to suspend the game.

Jordi Turull, the spokesman for the Catalonia regional government, said the Spanish government would end up responding to the international courts over the violence.

He described the actions of the Spanish state as "the shame of Europe".

The deadline for voting is 20:00 local time (18:00 GMT), but Mr Turull said that anyone in the queue at that time would be allowed to vote.

He said he did not know when the vote count would be finalised.

Why is a vote being held?

Catalonia, a wealthy region of 7.5 million people in north-eastern Spain, has its own language and culture.

It also has a high degree of autonomy, but is not recognised as a separate nation under the Spanish constitution.

The ballot papers contain just one question: "Do you want Catalonia to become an independent state in the form of a republic?" There are two boxes: Yes or No.

Pressure for a vote on self-determination has grown over the past five years.

But Spanish unionists argue Catalonia already enjoys broad autonomy within Spain, along with other regions like the Basque Country and Galicia.

Why is Madrid so opposed?

Spanish Prime Minister Mariano Rajoy says the vote goes against the constitution, which refers to "the indissoluble unity of the Spanish nation, the common and indivisible homeland of all Spaniards".

Central government spokesman Iñigo Mendez de Vigo accused the Catalan government of being inflexible and one-sided, but it is a charge that Catalan nationalists throw back at Madrid itself.

Before Sunday, demonstrations by independence campaigners had been largely peaceful.

Thousands of extra police officers were sent to the region, many of them based on two ships in the port of Barcelona.

The Spanish government has put policing in Catalonia under central control and ordered the regional force, the Mossos d'Esquadra, to help enforce the ban on the illegal referendum.

Before the poll, Spanish authorities seized voting materials, imposed fines on top Catalan officials and temporarily detained dozens of politicians.

Police have also occupied the regional government's telecommunications centre.

What happens next?

By Tom Burridge, BBC News, Barcelona

The Spanish government has always said that it's the Spanish courts ordering the Spanish police to act.

But their strategy today of physically preventing people from voting has the potential to backfire hugely.

Had you asked me 24 hours ago whether or not I thought it realistic that Catalonia's regional government would declare independence from Spain in the next few days I would have said probably not.

But after the very ugly scenes we've seen across this city and this region today I think it is a very real possibility.

Spanish riot police burst into polling stations across Catalonia on Sunday, confiscating ballot boxes and voting papers to try to halt a banned referendum on a split from Spain as Madrid asserted its authority over the rebel region.

The Mayor of the regional capital Barcelona Ada Colau issued a statement demanding “an immediate end to police charges against the defenceless population”. Madrid said its police had acted in a proportionate manner.

Police broke down doors to force entry into voting stations as Catalans shouted “Out with the occupying forces!” and sang the anthem of the wealthy northeastern region. In one incident in Barcelona, police fired rubber bullets.

Officers in riot gear hit people with batons and forcibly removed would-be voters, including women and the elderly, from polling stations.

Catalan officials said over 460 people had been injured in the police crackdown and the Spanish Interior Ministry said 12 police had been hurt.

Central government’s representative in Catalonia Enric Millo, referring to police action, told a news conference: “We have been made to do something we didn’t want to do.”

The referendum, declared illegal by Spain’s central government, has thrown the country into its worst constitutional crisis in decades and deepened a centuries-old rift between Madrid and Barcelona.

It remained unclear what action the Catalan government might take. However much voting takes place, a “yes” result is likely, given that most of those who support independence are expected to cast ballots while most of those against it are not

Despite the police action, hundreds-strong queues of people formed in cities and villages throughout the region to cast their votes. At one Barcelona polling station, elderly people and those with children entered first.

“I‘m so pleased because despite all the hurdles they’ve put up, I’ve managed to vote,” said Teresa, a 72-year-old pensioner in Barcelona who had stood in line for six hours.